The present invention relates generally to torque wrenches, and more particularly, to a novel and slidably adjustable torque wrench assembly that is designed to simultaneously tighten more than one bolt, nut, screw or the like.
A variety of torque wrench constructions are well known in the art. Such wrenches have been used in various mechanical assembling operations to tighten nuts and bolts rapidly and at the same time. Multi-drive shaft torque wrenches are also known, and are constructed and used with the objective of trying to ensure that the particular parts, such as couplings, brackets in plumbing or automobile operations and/or automobile wheels, are joined together or mounted without having to apply an excessive degree of unbalanced pressure or torque to any one bolt or nut, which tends to weaken or fracture the threads thereof. Other damaging effects of such unequal or unbalanced tightening may be the bending, weakening or fracturing of the coupling, brackets, etc. which are held together by the parts being tightened. That is, for example, the prior art recognized that when fasteners on a plumbing coupler are not tightened simultaneously it can cause the coupler to buckle on one side and increase the risk of leaking. Attempts to address and overcome the problem of being able to clamp, tighten or join an object, such as a wheel or the like by using more than one fastener at a time are well known and are described in patents such as U.S. Pat. No. 5,074,170.
Unfortunately, it is perceived that the state of the art multi-drive shaft torque wrenches are still less then desirable. One main perceived drawback in the prior art is the inability to adjust the distance between the drive shafts onto which sockets (or the like) are mounted. For example, U.S. Pat. No. 5,074,170, describes a lug nut tool 1 that uses and needs an intermediate gear 2 to rotatably couple the various drive shafts, and is exemplary illustrated in the present application as FIG. 4. For example, the inner center shaft, such as that coupled to gear 3, is coupled to the outer drive shaft 4 via intermediate gear 2. As such, it can be readily seen that such a device is unusable for any lug nut configuration different from the standardized configuration provided for in the described lug nut tool of FIG. 4. For example, moving gear 5 away from intermediate gear 2 clearly will cause the disengagement therebetween and quite obviously, lug nut tool 1 does not appear to lend itself to permit gear 5 to move any closer to gear 3.
Based thereon, the present inventor believes that further developments in the state of the art multi-shaft torque wrenches are desirable. For example, it is believed to be desirable to have a torque wrench assembly in which the position of one or more of the drive shafts is slidably adjustable relative to each other. The invention disclosed herein achieves the objectives and advantages set forth and overcomes the aforementioned perceived drawbacks.
It is an object and advantage of the present invention to provide a novel torque wrench assembly that simultaneously tightens one or more fasteners to a predetermined torque specification.
Yet another object of the invention is to provide a novel torque wrench assembly in which the drive shafts thereof are slidably adjustable so as to provide a unique and widely utilizable invention that can be appreciated and utilized in a variety of operations, such as in connection with the plumbing or automobile industry and in connection with a variety of configurations of fasteners, such as lug nuts, clamps, plumbing fixtures, just to name a few by way of example and not limitation.
It is a further object of the present invention to provide such a torque wrench assembly that can be handheld and easily operated.
Further objects and advantages of this invention will become more apparent from a consideration of the drawings and ensuing description.
The objects and advantages are realized by a torque wrench assembly constructed in accordance with embodiments of this invention, wherein such a torque wrench assembly is disclosed.
Generally speaking, the present invention is directed to a torque wrench assembly comprising a housing; a transfer shaft at least a portion of which is positioned in the housing, a first drive gear arrangement coupled to the transfer shaft; at least a second drive gear arrangement slidably coupled to the transfer shaft; a first drive shaft coupled to the first drive gear arrangement and having an end extending from the housing; a second drive shaft coupled to the second drive gear arrangement and having an end extending from the housing; a torque generating device that is coupleable to the transfer shaft, the first drive shaft or the first drive gear arrangement; whereby the distance between the first drive shaft and the second drive shaft is slidably adjustable by the slidability of the at least second drive gear arrangement along the transfer shaft; and the coupling of the first drive gear arrangement and the at least second drive gear arrangement via the transfer shaft provides that the first and second drive shafts are able to provide an at least an essentially equal torque.
In one preferred construction, the first drive gear arrangement is positioned within a first gear housing and the second drive gear arrangement is positioned within a second gear housing. Further, the first drive gear arrangement preferably comprises a first worm gear mounted on the transfer shaft and a second worm gear orthogonally aligned with and rotatably coupled to the first worm gear, and the second drive gear arrangement preferably comprises a third worm gear mounted on the transfer shaft and a fourth worm gear orthogonally aligned with and rotatably coupled to the third worm gear, such that the first drive shaft is coupled to the second worm gear and the second drive shaft is coupled to the fourth worm gear, all .of which is by helical threads on the outer surface of the worm gears.
Preferably, the housing includes a cavity; and at least the second drive gear arrangement is slideably disposed within the cavity and slides therein thus enabling the increase and decrease of the distance between the first drive shaft and the second drive shaft. In one configuration, the first drive shaft extends through a bottom of the housing and is coupled to the torque generating device. The torque generating device may include an adapter that is directly coupled to the first drive gear arrangement. In another embodiment, and end of the transfer shaft may extend outside of the housing and the torque generating device is coupled thereto, such as by utilizing an adaptor, for example. In such a configuration, both drive gear arrangements can be slideable. In one example, the torque generating device is a ratchet wrench.
A coupling arrangement that utilizes the present invention for use with the torque generating device is also specifically disclosed and claimed.